Outdoor heat



Feb. 12, 1963 Filed Aug. 16,

R. E. JA PHET SELF-POWERED FORCE FEED HEAT PUMP CDLD MIX'I'URE GAS lLLIQUD 2 Sheets-Sheet l FIG.|

COOLI N G' CYC LE LlQuln WATER IN losF. WATER 00T IloR 4 SEPARATQRRECEIVER (la a.)

MIXED G-AS s LIQUID LIQUID 90 FSIG-.To 35 PSI 6.

FIC-n2.

HEATING CYCLE RICHARDEJAPHET 1N V EN TOR.

Rl-:ElvER (ma) United States Patent @dice 3,077,087 SELF-PWERED FORCEFEED HEAT PUMP Richard E. laphet, Coytesville, NJ., assigner toWorthington Corporation, Harrison, NJ., a corporation of Delaware FiledAug. 16, 1961, Ser. No. 131,915 6 Claims. (Cl. 62-324) This inventionrelates generally to heat pumps and more particularly to a force feedtype heat pump system which employs the inherent thermodynamiccharacteristics of the high to low side pressure differential as themotive power for the force feed circulation of the low pressure sidecycle.

In my copending U.S. application Serial No. 107,181, iiled May 2, 1961,a new and improved heat pump system was described, characterized by thefact that the compressor functioned in a condensing or high pressureside cycle and a pump functioned in an evaporating or low pressure sidecycle, which cycles were relatively independent but coacted by means ofa common accumulator or the like separating means.

In the force feed heat pump system shown in my copending application itwas inherent in the structure shown that the pump would ybe operated bya conventional means such as an electric motor or other independentprime mover.

it is known, however, as shown in Patents 2,156,096, 2,519,010,2,737,031 and 2,986,898 that in conventional refrigerant cycles motivepower can be obtained from the pressure drop of the refrigerant liuid asit passes from the condensing cycle to the evaporating cycle of therefrigerant arrangement.

This broad principle is particularly applicable to the heat pump systemshown and described in my copending application U.S. Serial No. 107,181.The addition of this principle to such heat pump system has two mainadvantages.

(a) It simplifies the system in that the use of the relirigerant fluidto operate the lluid operated driver permits the driver to act as anexpansion device thus eliminating either the low pressure tloat valve,iioat valve mechanism or the high pressure float valve metering deviceas is required in the system shown in the copending application.

(b) lt eliminates the conventional prime mover for at least theimportant heating and cooling cycles, which in turn increases theefficiency of the system by the power consumption factor of suchconventional prime mover.

Thus, the present invention covers an improved heat pump having acooling and a heating cycle wherein cornpression means functions in acondensing or high pressure side cycle and pump means functions in anevaporating or low pressure side cycle, which cycles are relativelyindependent but coact through a common separating means and wherein thehigh pressure refrigerant from the high pressure side cycle is at alltimes delivered for expansion to a suitable iluid operated driver havingits outlet connected to said separating means which driver provides themotive power for the pumping means operating in the low pressure sidecycle.

Accordingly, it is an object of the present invention to provide a forcefeed type heat pump system which is relatively simple and employs theinherent thermodynamic characteristics of the refrigerant iluid as itchanges pressure and phase.

It is another object of the present invention to provide a heat pumpsystem wherein the conventional prime mover such as an electric motorwill be eliminated from the system and the driving means of the pumpwill be operated by the refrigerant of the system itself.

Further objects and advantages of the invention will 3,077,637 PatentedFeb. 12, 1953 become evident from the following description withreference to the accompanying drawings in which:

FIGURE 1 is a diagrammatic sketch of the invention showing a coolingcycle including an outdoor heat exchanger in heat exchange communicationwith atmospheric air.

FIGURE 2 is a diagrammatic sketch of the invention showing a heatingcycle including an outdoor heat exchanger in heat exchange relation withatmospheric air.

FIGURE 3 is a diagrammatic sketch showing a system in accordance withthe invention having an auxiliary pump to provide an intermediatecooling cycle.

FIGURE 4 is a diagrammatic sketch showing the invention with the uidoperated driver and pump disposed outside of the separating means.

FIGURES 1 and 2 illustrate diagrammatically arrangements of the sameelements in the form of a heat pump in accordance with the presentinvention. They are distinguished in that the refrigerant temperature,pressure and flow path between the elements differ for the respectivecooling and heating cycles.

While in the heat pump system illustrated one heat exchanger is shown inheat exchange relation with atmospheric air, it will be understood thatsuch heat exchanger could be associated with other heat sink or heatsource media as will be understood by those skilled in the art and thatthe corresponding heat exchanger best for the medium serving as the heatsink or heat source will be utilized.

Furthermore, while the system shows a. second heat exchanger in heatexchange relation with circulating water to be heated or cooled, it willbe understood that heat exchange can be with other liquid media or withair or other gaseous media without departing from the scope of thepresent invention.

General Arrangement of the Hear Pump Referring to FIGURES l and 2 wherethe same parts will have the same character numerals, a compressor isshown at 1 having a discharge outlet 2. connected to a discharge line 3disposed to receive hot compressed gaseous refrigerant from thecompressor. The discharge line 3 is connected to three conduits 4i., Sand 6 each having a respective solenoid operated valve '7, 8 and 9 whichcan be manually or automatically controlled to provide that direction ofiiow in the system which will produce the desired cooling, heating ordefrost cycles. Only the cooling and heating cycles will be described inthe present application because the defrost cycle is fully described inmy above identified copending application and therefore does not requirefurther comment herein.

Conduit 4 communicates with an inlet header 10 of a first heat exchanger11 which will be called for the purpose of the present disclosure theoutdoor heat exchanger because it is disposed and located so thatatmospheric air can be passed thereover as by a fan 12 to permit goodheat exchange relation to occur between the coils 13 of the heatexchanger and the air. Heat exchangers for this purpose are well knownand are easily purchasable on the open market.

As indicated above this heat exchanger may for all purposes also be onewhich is adapted for heat exchange relation with other types of heatsink and heat source media.

The outlet header A1e of the first or outdoor heat exchangercommunicates to connecting line 15 and common conduit 16 directly withthe inlet 17 which is connected to an automatically operable lluiddriver and pump arrangement generally designated 18 mounted by anysuitable means in a separating means or accumulator 19 which driver andpump arrangement is operable by expansion of the high pressure liquidrefrigerant delivered through the inlet line 17 and serves for pumping10W pressure liquid refrigerant from the Separating means 19 through thelow side cycle of the heat pump system as is more fully describedhereinafter.

The uid driver may be either the expansion turbine type depicteddiagrammatically in FIGURES 1 and 2 of the drawings, a sliding vane typeor other suitable driver adapted to be operated by expansion ofrefrigerant huid. Similarly the pump may be either the centrifugal typeshown in FIGURES 1 and 2, a positive displacement type or other suitablepump for delivering the liquid t the low pressure side cycle.

Such devices and pumps are purchasable on the open market, hence, itwill be understood by those skilled in the art that any combination ofdriver and pump for accomplishing the desired result may be used withoutdeparting from the scope of the present invention.

Furthermore, even though in the illustrated form of the invention thecombined driver and pump are shown mounted in the separating means d?,it is believed that those skilled in the art will understand that thisis a matter of practical expediency because it eliminates the necessityfor seals and the driver and pump arrangement can be mounted outside ofthe separating means as is shown in FIGURE 4 but in this latterarrangement in order to obtain the same advantage relative the sealproblem the combination unit will have to be hermetic.

Separating means 19 will also be sized sufficiently large both toaccommodate the combined fluid driver and pump arrangement 18 and topermit a proper separation 0f the gaseous and liquid refrigerant whichis delivered to the accumulator and shall be constructed to act as ahigh pressure receiver for storing the entire charge of the refrigerantas may be necessary during shutdown or repair periods. The receiver 19ais also provided for overflow and storage.

The combined fluid operated driver and pump arrangement 1S as shown inFIGURES l and 2 includes an integral casing 2t? forming a pump 21 at oneend and a duid operated driver 22 at the other end.

The casing 2t? includes a common shaft 23 which extends through thecasing from a pumping chamber 2d for the pump 2. to a rotor chamber 2,5for the fluid operated driver 22 where the respective ends of the shaftreceive a pump impeller 26 and a rotor 27.

The rotor is driven by high pressure liquid refrigerant deliveredthrough the nozzle 255 which communicates with the end of the inlet line17 remote from the end connected to the common line 16.

The rotor chamber' 25 is shown as having a discharge outlet 29 whichdischarges directly to the separator or accumulator i9. It is believedthat those skilled in the art will understand that when high pressureliquid refrigerant expands through the nozzle 28 and expends energy todrive the rotor 27 that the pressure and temperature of the liquidrefrigerant will drop and as a result a partial phase change will occuron the discharge outlet side of the rotor 27 so that a mixed gaseous andliquid phase of refrigerant will be discharged from the discharge outlet29 into the separator 19 Where by reason of the sizing of the separatorwill separate into the respective liquid and gaseous phases by theeifect of gravity and difference in mass as indicated by the liquidlevel line therein.

As a result, if the combined fluid operated driver and pump arrangement18 is so disposed that at least the pump 21 is submerged in therefrigerant liquid, then when the impeller 26 which is connected bycommon shaft 23 to the rotor Z7 rotates liquid refrigerant can be drawnin through the suction inlet 30 O-f the pumping chamber and dischargedthrough the discharge outlet 31 for the pumping chamber to deliverrefrigerant liquid at low pressure to the outlet connecting line 32which extends through the wall of the separator 19 to deliver lowpressure refrigerant liquid to the low side cycle as is more fullydescribed hereinafter.

The gaseous refrigerant in separator 19 will be drawn of through suctionline 33 to the suction inlet 34 for the compressor 1 when the compressoris in operation so that the slugging of liquid is always avoided duringthe operation of the compressor.

Conduit 6 in turn communicates with the inlet header 40 of a second heatexchanger 41 which is termed for the purposes of the kpresentdescription as the indoor heat exchanger because it will be disposed atan enclosed point such that either a liquid or a gas may be circulatedthrough the coils 42 to provide means for transferring heat orabstracting heat depending on the cycle in operation at the time thatrefrigerant is flowing through the coils. This is accomplished in thepresent form of the invention by passing liquid through the coolingfluid inlet 43 and removing it by outlet 44 to the point where theliquid can be utilized. Heat exchangers for this purpose are Well knownin the air conditioning and refrigeration art and are easily purchasable0n the open market, hence are not more fully described herein.

The outlet header 45 for the second or indoor heat exchanger 41 is alsoconnected through return line 46 to the common line 16 and FIGURES l and2 show that the conduits 15 and 46 are provided with check valves as at47 and 48 respectively so that the flow of refrigerant fluid through theoutdoor and indoor heat exchangers will be unidirectional at all timeswhich condition of 0peration is a specific characteristic of the presentinvention regardless of the particular cycle of operation.

FIGURES l and 2 also show that lines 15 and 46 cornmunicate throughlines 49 and 50 respectively directly to a common collecting line Srland depending on the operating cycle which signals the automatic ormanual setting for control valves 52 and 53 for the respective lines 49and S0, refrigerant gas and liquid from one or the other of the heatexchangers 11 or 41 can bypass the common conduit 16 and be passeddirectly to the separator or accumulator 19.

The operation of valves 7, Y8, 9, 52l and 53 may be manual or automaticand any suitable type of conventional solenoid or the like typepneumatically or electrically operated controls.

Pumping Cycle In order to provide the positive or force feedingcirculation of refrigerant liquid to the respective indoor and outdoorheat exchangers in the heating or cooling cycle hereinafter describedwhere the heat exchanger is not receiving hot compressed gaseousrefrigerant, the pump 21 delivers low pressure refrigerant liquidthrough outlet line 32 connected to the conduits 55 and 56 which are inturn connected to the conduits 4 and 6 leading to the heat exchangers 11and Ail. Conduits 55 and 56 are provided with their respective checkvalves 57 and 5S which check valves act to direct the flow ofrefrigerant liquid depending on the setting of the control valves 7 and9.

It is readily .apparent that the operation of the check valves S7 `and5S will be similar to that of the check valves 47 and 4S which depend onthe setting of the control valves 52 and 53.

In both the case of the check valves 57 yand 5S and check valves 47 and48 the pressure of the refrigerant will pressurize one or the other ofthe check valves so that the ow will occur through that check valvewhich does not have pressure acting against its discharge side.

The valves 52 #and `53 also permit the inclusion of the defrosting cyclewhich is accomplished through the defrosting conduit 5 connected to thecommon discharge line 3 from the compressor `and to a point downstreamof the solenoid operated valve 7 and the check valve 57, whichdefrosting cycle is fully described in my copending application andhence is not referred to further herein `as it forms no part of thepresent invention.

Also described in my copending application is an oil recoveryarrangement which includes a valve 60. This system is also not describedin the present application as it forms no part of the present invention.

Cooling Cycle Cooling of ya liquid or gaseous medium in heat exchangerelation with the indoor heat exchanger 41 can be obtained by operatingthe heat pump in the following manner:

First, the compressor 1 and the fan 12 are placed into operation. Valves7, 53 and 60 will be open and all other valves will be closed. Hotcompressed gaseous refr-igerant from the compressor 1 will now passthrough the discharge outlet 2 and common discharge line 3 to theconduit 4 connected to the inlet header 10 of the outdoor heat exchanger11. ln the outdoor heat exchanger 11 the hot compressed gaseousrefrigerant will b-e condensed to provide a hot liquid refrigerant whichwill collect in the outlet header 14 of the outdoor heat exchanger 11.

The hot liquid refrigerant passes from the outlet header 14 throughlines 1S and 16 to the yinlet line 17 which communicates with the nozzlein the rotor chamber 25. The hot liquid refrigerant expands through thenozzle and provides the motive power for rotating the rotor 27 and isdischarged through the discharge outlet 29 as ya mixture of relativelycold gas and liquid refrigerant into the separator or accumulator 19where t-he gaseous liquid refrigerant by reason of the sizing of theseparator separates so that a gas layer occupies the upper portion ofthe accumulator and a liquid layer occupies the lower portion of theaccumulator as indicated by the liquid level line in FIGURE 1.

Suction line 33 of the compressor is connected to the upper portion ofthe accumulator which holds the gaseous refrigerant. Therefore, only gaspasses through the suction line 33 and the suction inlet 34 of thecompressor Where it is once again recompressed to repeat .the condensingor high side cycle above described.

Since the fluid operated driver and pump operate automatically Wheneverthe rotor is energized under the action of the expanding hot refrigerantliquid the relatively cold liquid refrigerant in the accumulator 19 willbe pumped with positive pressure to the indoor heat exchanger 41. Thuspump 21 receives liquid through the suction inlet 30 into the pumpchamber 24 and discharges the refrigerant liquid through line 32 to theconnecting conduits 55 and 56. Due to the fact that hot compressedgaseous re frigerant is passing through conduit 4 the check valve 57 isprevented from opening and liquid refrigerant from the pump 21 must bedelivered through conduit 56 and check valve 58 to the conduit 6connected to the inlet header 4d of the indoor heat exchanger 41.

At the indoor heat exchanger the liquid refrigerant is passedtherethrough into heat exchange relation with fluid to tbe cooled whichis delivered through line 43 and removed by line 44 so that part of thecold liquid refrigerant is evaporated as it cools the uid being passedthrough the indoor heat exchanger. This -cooled iiuid media `as itleaves line 44 may be passed to any suitable point of use.

It is believed clear to tho-se skilled in the air conditioning andrefrigeration `art that air or other gaseous media could also be cooledby passing it in heat exchange relation with a suitable type indoor heatexchanger without departing from the scope of this invention.

The refrigerant collected in the outlet header 45 of the heat exchanger41 will be part gas and part liquid because the pump supplies a greaterquantity of liquid than is required for the capacity of the heatexchanger. This is advantageous because the inner surfaces of the tu-besof the heat exchanger will under these conditions be continually wetted`thereby increasing the efficiency `of the heat exchanger.

This mixture of gaseous and liquid refrigerant will be passed from theoutlet header 45 through lines 46 and 50 and control valve 53 to line 51into the separator or accumulator 19 where it joins with alike mixtureas gas and 6 liquid from the discharge outlet 29 of the :duid driver 22Where it is separated by gravity as indicated by the liquid level lineshown.

This pump circulation cycle will operate continuously to provide thedesired cooling as long as the compressor continues to operate with thevalve set for the cooling cycle as above described.

Heating Cycle In the heating cycle shown in FIGURE 2 the compressor 1and the fan 12 are first placed into operation, all valves are closedexcept control valves 9, 52 and 60.

With this arrangement of the control valves hot compressed gaseousrefrigerant Will be discharged from the compressor through dischargeoutlet 2 and discharge line 3 to the conduit 6 and will be passed byconduit 6 to the inlet header 40 of the indoor heat exchanger 41 whereit gives up heat to the medium to be heated as, for example, waterbrought into the heat exchanger 41 through the inlet 43 and dischargedto the desired point of use through outlet 44 in its heated condition.lt is understood that heat exchange could be made with other liquidmedia or air or other gaseous media without departing from the scope ofthis invention and that where air or a gas media is used that the typeheat exchanger required for this rnedia will also be used as is wellknown in the heat pump art.

The release of heat to the media to be heated causes the gas to condenseto provide hot liquid refrigerant, which hot liquid refrigerant passesthrough the outlet header 45 of the heat exchanger 41 through line 46and check valve 48 to the common line 16 leading into the inlet line 17of the combined fluid operated driver and pump device 13.

The hot refrigerant liquid expands and releases its energy to place therotor 27 into operation so that relatively cool gas and liquidrefrigerant will be passed from the discharge outlet 22 to the separatoror accumulator 19 where by reason of the size of the accumulator therefrigerant mixture separates as by gravity to provide a gaseous layerand a liquid layer of the refrigerant in intimate contact with eachother as indicated by the liquid level line in FIGURE 2.

Since the suction line 33 communicates with the gaseous portion of therefrigerant in the separator 19 the compressor will draw gaseousrefrigerant through the suction inlet line 33 and suction inlet 34 intothe compressor where it will be recompressed and passed through thecycle above described.

In addition to the heat of compression heat is also drawn from the heatsource in Contact with the outdoor heat exhanger 11 by force feedingcold refrigerant liquid to this outdoor heat exchanger by means of thepump circulation cycle.

Thus, pump 21 operating automatically whenever the rotor 27 of the fluidoperated driver 22 is energized will receive liquid refrigerant from theseparator 19 through its suction inlet 30 where it passes through thepump chamber 24 and is discharged through line 32 to the connectingconduits 5S and 56.

Due to the fact that hot compressed gaseous refrigerant is passingthrough conduit 6 the check valve 58 in the line 56 is prevented fromopening and liquid refrigerant from pump 21 must be delivered to conduit55 and check valve 57 to the conduit 4 connected to the inlet header 10of the outdoor heat exchanger 11.

As this cold liquid refrigerant passes through coil 13 of the outdoorheat exchanger 11 the liquid refrigerant which will always be colderthan the heat source will pick up heat from the heat source and thenfrom the outlet header 14 of the outdor heat exchanger 11, will bepassed through line 15 and line 49 and control valve S2 to thecollecting line 51 which delivers the mixture of gas and liquidrefrigerant to the separating means 19 where it separates into gas andliquid layers similar to the separation of the mixture discharged fromoutlet 29 as indicated by the liquid 'level line and as above describedrecirculated through lines 32 and 33 for the compressor and suctioninlet for the pump respectively to repeat the cycle above described.

The construction thus described of the present invention While operatingsubstantially similar to that of the construction described in mycopending application Serial No. 107,181 differs in that it utilizes thcinherent thermodynamic characteristics of the high to low side pressuredifferential as 'the motive force for the force feed circulation of thelow pressure side cycle which system is not only simpler in constructionbut further has a materially increased efficiency thereover by the powerconsumption factor of the conventional prime mover required in suchsystems.

Intermediate Cycle It is apparent that the motive force for the pump 21depends on the continuous operation of the compressor 1. However, thepresent invention can be easily adapted to provide an intermediatecooling cycle identical with that described in my copending applicationSerial No. 107,181 if the system is modified as shown in FIGURE 3 of thedrawings.

In FIGURE 3 identical parts have been given identical numbers and theoperation is identical with that above described for the respectivecooling and heating cycles.

However, by adding an auxiliary pump as at 7d operated by anyconventional form of prime mover 71 if the suction inlet of the pump isconnected to the separator 19 and the discharge outlet is connected toline 55 it is believed clear that iluid can be delivered independentlythrough the respective conduits by this auxiliary pump when thecompressor is not in operation.

Thus, for the intermediate cooling cycle where cooling is effected by amixing process, the heat content of two portions of the refrigerant ischanged by circulation. One portion discharges heat to the heat sink andthe other absorbs heat from the media to be cooled, the respectiveportions then being mixed together for recirculation through the systemonce again by means of the separator 19.

This operating cycle is designed for very limited conditions where somebut not a large quantity of cooling is required and the circulation canof course 'oe either in parallel as shown in FIGURE 3 or the drawings orin series as is indicated in my copending application Serial No.107,181.

Thus by reference to FIGURE 3 which shows a parallel arrangement we findthat in this cycle only the pump 7d and the fan 12 will be in operation.The compressor will not be in operation. in addition valves '7, S, 3-and 60 will be closed and valves 52 and 53 will be open.

In operation pump 7d draws refrigerant liquid from the separator 19 anddischarges the liquid under pressure through lines 55 and 56simultaneously into conduits 4 and 6 respectively which in turn directthe liquid refrigerant to the inlet header 10 for the heat exchanger l1and the inlet header di) for the heat exchanger 41.

Refrigerant liquid in heat exchanger' 11 will pass through the coils 13and on contacting heat exchange relation with air passed thereacross bythe fan 12 and thus will be cooled. The cool refrigerant collects in theoutlet header 14 and is passed via lines l5 and dit and collecting line51 to the separator 19.

Similarly liquid refrigerant in heat exchanger 41 will pass through itscoils in non-contacting heat exchange relation with the media be itliquid or gas or other fluid to be cooled as, for example, water whichis introduced through inlet 43 and discharged through outlet i4 of theheat exchanger 41 which cooi liquid can be utilized for cooling at anysuitable point.

The heat exchange relation in heat exchanger d1 delivers a mixture ofgas and liquid refrigerant to the outlet header of the heat exchanger l1which mixture flows via lines 46 and 50 and control valve 53 to thecollecting line 51 which communicates with the separator 19 where itmixes with the cool liquid refrigerant returning from the heat exchanger11. Mixture of the two provides a refrigerant having an ambienttemperature which will once again permit it to absorb heat from themedia to be cooled by repetition of the full cycle above described.

Where the intermediate cooling cycle is accomplished by series ow thesystem must be modied as shown in FIGURE 6 of my copending applicationSerial No. 107,181 and since it has been fully described therein it isnot deemed necessary to repeat the description of the series cycle forthe purposes of the present invention.

Modified Form of the Invention FGURE 4 shows a modified form of theinvention and differs from the form of the invention shown in FIG- URESl and 2, only to the extent that the combined fluid operated driver andpump arrangement is disposed exteriorly of the separator.

ln FiGURE 4 identical parts have been given identical numbers and theoperation of these parts is substantially identical with those abovedescribed for the cycles of the invention shown in FIGURES 1 and 2..

By reference to FIGURE 4 line 16 is connected to the inlet port 17 forthe automatically operable iluid driver and pump arrangement designated18.

The combined fluid operated driver and pump arrangement 18 as shown inFIGURE 3 is a hermetic unit and thus includes an integral casing 20forming a pump 21 at one end and the fluid operated driver 22 at theother end.

The casing 20 has a comm-on shaft 23' which extends `from the pumpingchamber 24' of the pump Z1' to the rotor chamber 25 for the fluidoperated driver 22 where the respective ends of the shaft receive a pumpimpeller 26 and a rotor 27.

Therotor is driven by high pressure liquid refrigerant, identical withthe form of the invention shown in FIG- URES l and 2, which is deliveredthrough the nozzle 28' connecting with the inlet port 17' remote fromthe end connected to common line 16.

The rotor chamber 25 is shown as having a discharge line 29a connectedto the return line 51 so that mixed gaseous and liquid refrigerant isreleased to the separator or accumulator@ for separation into layers asindicated by the liquid level line and for recirculation.

The pump Z1 is provided with a suction inlet 30' which connects suctionline 3%@ to the lower section of the separator 19, and will when rotatedwith .the rotation of rotor 27 discharge refrigerant liquid from thepumping chamber 2d through discharge outlet 31' for the pumping chamberand outlet line 32 connected in turn to conduits 55 and 56. y

Operation of this form of the invention will be identical with thatabove described lfor the cooling and heating cycles of FIGURES 1 and 2.This `form of the invention differs only to the extent that the driverand pump 18' are external of the separator 19, hence fluid dischargefrom the driver must pass through the lines 29a and 51 for dischargedirectly into the separator and the pump must direct fluid to thesuction inlet Bil via the line 30a connected to the lowermost portion ofthe separator 19.

it will be understood that this invention is not to be limited to thespecific construction or arrangement of parts shown but that they may bewidely modified within the scope of the invention defined by the claims.

What is claimed is:

y1. ln a heat pump, a'plurality of heat exchange means, separating meansfor storing and separating gaseous and liquid refrigerant, a iiuidoperated driver having an inlet and an outlet wherein the outlet isdisposed in operative relation to said separating means for deliveringfluid thereto, means connecting the downstream side of each heatexchange means to `the inlet of said fluid operated aoc/zoe? driver, acompression means, said compressi-on means having its suction connectedto said separating means and its discharge being connected to deliverhot compressed gaseous refrigerant interchangeably and selectively tothe upstream side of at least one of said heat exchange means, and apump circulation cycle having its suction connected to said separatingmeans to receive cold liquid refrigerant therefrom and to force feed anexcess of liquid refrigerant to the upstream side of at least one otherof said heat exchange means not receiving hot compressed gaseousrefrigerant from said compression means, said pump means connected toand operated by said iiuid operated driver.

2. ln a heat pump, a lirst heat exchange means and a second heatexchange means each having inlet means and outlet means, at least onecompressing means, at least one pumping means, means to interchangeablyand selectively connect the compression means and the pumping means tothe respective inlet means for the first and second heat exchange means,a common separating means for storing and separating gaseous and liquidrefrigerant, a uid operated device having an inlet and an outlet, meansconnecting the respective outlet means from said iirst and second heatexchange means to the inlet for said fluid operated device to expandrefrigerant therethrough for driving said fluid operated device, saidseparating means in communication with the outlet of said fluid operateddevce to receive expanded refrigerant therefrom, said compression meanshaving its suction connected to said common separating means to receivegaseous refrigerant therefrom and to pass hot compressed gaseousrefrigerant to that heat exchange means selectively connected to thedischarge of the compression means, and said pumping means having itssuction connected to said common separating means to receive cold liquidrefrigerant therefrom and to pass any excess of liquid refrigerant underpressure to that heat exchange means selectively connected to thedischarge lof the pumping means, and said liuid operated deviceoperatively connected to said pump to provide the motive power fordriving said pump.

3. In a heat pump having a heating and a cooling cycle, a high pressureside cycle including, compression means and at least one heat exchanger,a low pressure side cycle including pump means and at least one otherheat exchange means, means interchangeably and selectively connectingthe compression means discharge to the upstream side of saidfirst-mentioned heat exchange means and to the upstream side of saidsecond heat exchange means for delivering hot compressed gaseousrefrigerant thereto, means interchangeably and selectively connectingthe pump means to the upstream side of said first-mentioned heatexchange means and to the upstream side of said second heat exchangemeans for delivering cold liquid refrigerant from said pump means to therespective heat exchange means, a common separating means for storingand sepaarting gaseous and liquid refrigerant, a Huid operated devicehaving an inlet and an outlet, means connecting the downstream side ofsaid first heat exchange means and said second heat exchange means tothe inlet of said liuid operated device delivering hot liquidrefrigerant at high pressure to said inlet for expansion in the liuidoperated device, said fluid operated device having its outlet connectedto deliver mixed low pressure gaseous and liquid refrigerant to theseparating means, lsaid compression means having its suction inletconnected to said common separating means and its discharge outletconnected to said means for interchangeably and selectively del-iveringhot compressed gaseous refrigerant .to the upstream side of therespective first and second heat exchange means, and said pump meanshaving its suction connected to said common separating means and itsdischarge connected to said means for delivering cold liquid refrigerantto said first and second heat exchange means and at al1 times to deliveran excess of liquid refrigerant to the respective heat exchange meansconnected thereto for the particular cycle of operation, and said pumpmeans connected to and operated by said fluid operated device.

4. In the heat pump as claimed in claim 3 wherein the liuid operateddevice is disposed in said separating means.

5. In the heat pump as claimed in claim 3 wherein the tiuid operateddevice and pump are combined in a single operating unit, and saidcombined fluid operated driver and pump are mounted in said separatingmeans.

6. In a heat pump as claimed in claim 3 including an auxiliary pumpingmeans, a conventional driver for operating said auxiliary pumping means,said pumping means having an inlet and an outlet, and said pumping meansdisposed to permit the inlet to receive liuid from said separating meansand to discharge said refrigerant iuid .to the upstream side of saidrespective heat exchangers, and said auxiliary pumping means disposed tooperate independently and without the compressor to selectively deliverrelatively cold liquid refrigerant from the separating means to therespective heat exchangers yfor providing an intermediate cooling cyclewhen the same is required.

References Cited in the tile of this patent UNITED STATES PATENTS2,394,109 Sanchez Feb. 5, 1946 2,494,120 Ferro Jan. 10, 1950 2,576,663Atchison Nov. 27, 1951 2,724,240 Sloan Nov. 22, 1955

1. IN A HEAT PUMP, A PLURALITY OF HEAT EXCHANGE MEANS, SEPARATING MEANSFOR STORING AND SEPARATING GASEOUS AND LIQUID REFRIGERANT, A FLUIDOPERATED DRIVER HAVING AN INLET AND AN OUTLET WHEREIN THE OUTLET ISDISPOSED IN OPERATIVE RELATION TO SAID SEPARATING MEANS FOR DELIVERINGFLUID THERETO, MEANS CONNECTING THE DOWNSTREAM SIDE OF EACH HEATEXCHANGE MEANS TO THE INLET OF SAID FLUID OPERATED DRIVER, A COMPRESSIONMEANS, SAID COMPRESSION MEANS HAVING ITS SUCTION CONNECTED TO SAIDSEPARATING MEANS AND ITS DISCHARGE BEING CONNECTED TO DELIVER HOTCOMPRESSED GASEOUS REFRIGERANT INTERCHANGEABLY AND SELECTIVELY TO THEUPSTREAM SIDE OF AT LEAST ONE OF SAID HEAT EXCHANGE MEANS, AND A PUMPCIRCULATION CYCLE HAVING ITS SUCTION CONNECTED TO SAID SEPARATING MEANSTO RECEIVE COLD LIQUID REFRIGERANT THEREFROM AND TO FORCE FEED AN EXCESSOF LIQUID REFRIGERANT TO THE UPSTREAM SIDE OF AT LEAST ONE OTHER OF SAIDHEAT EXCHANGE MEANS NOT RECEIVING HOT COMPRESSED GASEOUS REFRIGERANTFROM SAID COMPRESSION MEANS, SAID PUMP MEANS CONNECTED TO AND OPERATEDBY SAID FLUID OPERATED DRIVER.